Company · Ownership research

MAGNITE, INC. MGNI

CIK 0001595974 · CUSIP 55955D100

Insider trading Initial holdings Institutional holders

Quarter-end disclosures, not live holdings.

Several CUSIPs are reported for this company; this page shows CUSIP 55955D100 (MGNI), not CUSIP 55955D900 (MGNI), CUSIP 55955D950 (MGNI), CUSIP SBLPNRR62 (MGNI), CUSIP 78112V102, and does not merge CUSIPs.

This page lists the top 20 of 297 rows by value; the complete set is available through the API.

Top 20 institutions

Weight means this stock's share of the manager's own portfolio.

By reported value

#	Manager	Value	Manager weight	Change vs prior	Source
01	BlackRock, Inc. CIK 2012383 · View history	$138.49M 11,657,496 shares	0.00%	+64.25K(+0.60%)Added	SEC filing ↗ May 13, 2026	▾
02	WELLINGTON MANAGEMENT GROUP LLP CIK 902219 · View history	$109.19M 9,191,077 shares	0.02%	+561.84K(+6.50%)Added	SEC filing ↗ May 15, 2026	▾
03	VANGUARD PORTFOLIO MANAGEMENT LLC CIK 2100121 · Amended · View history	$91.79M 7,726,205 shares	0.00%	—	SEC filing ↗ May 8, 2026	▾
04	VANGUARD CAPITAL MANAGEMENT LLC CIK 2100119 · Amended · View history	$73.54M 6,190,403 shares	0.00%	—	SEC filing ↗ May 15, 2026	▾
05	Capital Research Global Investors CIK 1422848 · View history	$59.64M 5,020,289 shares	0.01%	-7.90M(-61.10%)Reduced	SEC filing ↗ May 13, 2026	▾
06	Boston Partners CIK 1386060 · View history	$56.08M 4,719,863 shares	0.06%	+610.97K(+14.90%)Added	SEC filing ↗ May 11, 2026	▾
07	AMERICAN CENTURY COMPANIES INC CIK 748054 · View history	$54.97M 4,626,816 shares	0.03%	-660.11K(-12.50%)Reduced	SEC filing ↗ May 15, 2026	▾
08	FMR LLC CIK 315066 · View history	$53.55M 4,507,419 shares	0.00%	-2.19M(-32.70%)Reduced	SEC filing ↗ May 15, 2026	▾
09	DIMENSIONAL FUND ADVISORS LP CIK 354204 · View history	$47.32M 3,983,674 shares	0.01%	+367.85K(+10.20%)Added	SEC filing ↗ May 7, 2026	▾
10	Nuveen, LLC CIK 1871926 · View history	$42.65M 3,590,025 shares	0.01%	+58.92K(+1.70%)Added	SEC filing ↗ Apr 30, 2026	▾
11	GEODE CAPITAL MANAGEMENT, LLC CIK 1214717 · View history	$42.23M 3,553,790 shares	0.00%	+119.73K(+3.50%)Added	SEC filing ↗ May 15, 2026	▾
12	Nine Ten Capital Management LLC CIK 1635236 · View history	$41.36M 3,481,283 shares	13.14%	+477.70K(+15.90%)Added	SEC filing ↗ May 15, 2026	▾
13	STATE STREET CORP CIK 93751 · View history	$37.58M 3,163,139 shares	0.00%	+21.15K(+0.70%)Added	SEC filing ↗ May 15, 2026	▾
14	Edenbrook Capital, LLC CIK 1666682 · View history	$33.24M 2,798,036 shares	17.00%	+10.00K(+0.40%)Added	SEC filing ↗ May 14, 2026	▾
15	Granahan Investment Management, LLC CIK 1026710 · View history	$30.33M 2,553,413 shares	1.47%	-562.52K(-18.10%)Reduced	SEC filing ↗ May 15, 2026	▾
16	Ophir Asset Management Pty Ltd CIK 1844640 · View history	$25.16M 2,118,016 shares	2.93%	-266.17K(-11.20%)Reduced	SEC filing ↗ May 15, 2026	▾
17	325 CAPITAL LLC CIK 1873893 · View history	$23.82M 2,005,387 shares	8.68%	0(0.00%)Unchanged	SEC filing ↗ May 15, 2026	▾
18	KENNEDY CAPITAL MANAGEMENT LLC CIK 884589 · View history	$20.83M 1,753,542 shares	0.44%	+317.57K(+22.10%)Added	SEC filing ↗ May 13, 2026	▾
19	JANE STREET GROUP, LLC CIK 1595888 · View history	$19.82M 1,668,160 shares	0.02%	+1.29M(+338.70%)Added	SEC filing ↗ May 12, 2026	▾
20	No Street GP LP CIK 1765774 · View history	$19.34M 1,628,248 shares	1.29%	+153.25K(+10.40%)Added	SEC filing ↗ May 15, 2026	▾

Showing 20 / 297 institutions. The complete set is available through the API.

Coverage & totals by quarter

Reporting institutions

297

Cancelled or null records excluded

Disclosed shares

131,564,561

Not deduplicated across managers

Disclosed value

$1.56B

Not market cap or free float

Reporting institutions by quarter

Counts also change with data coverage and reporting entities; they do not measure net buying. Distinct managers with a live stock row in this CUSIP; totals may include overlapping filings and are not a share of the company.

MAGNITE, INC. · Q1 2026

Explore all 297 reporting institutions.

This page includes 20 of 297 reporting institutions. Log in to look up the full history beyond 3 years, use advanced screening & filtering, download CSV, and get the complete set through the Akkru API.

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Figures are as reported to the SEC and merged with later amendments where Akkru could match them. Preview limits apply to what is listed, not to the totals, which come from the complete reported data. Nothing is zero-filled: a missing quarter or month is shown as missing.